Valve for internal combustion engines



Dec. 22, 1936. F, E BULLOCK 2,065,049

VALVE FOR INTERNAL COMBUSTION ENGINES Filed April 11, 1935 Patented Dec.22, 1936 re'r oFFicE VALVE FOR ILEIE BNAL COWUSTION Application April'11, 1935, Serial No. 15,896 In Great Britain February 5, 1935 3 Claims.

This invention relates to valves of the poppet type as used in internalcombustion engines.

At the present time the high working temperatures which obtain ininternal combustion engines are a prevalent cause of valve fracture andit is the object of the present invention to provide means forpreventing the valves from becoming overheated.

For this purpose, metal having a high degree of heat conductivity, suchas copper, is applied to the exterior of the valve, i. e. between thevalve and the valve guide.

In the accompanying drawing:-

Figure 1 represents a poppet valve and one way of applying the heatconducting metal thereto.

Figure 2 illustrates a poppet valve in which the heat conducting metalis enclosed in a sleeve.

Figure 3 illustrates a poppet valve to which the heat conducting metalis applied in the form of a wire coil enclosed within a bush.

Figure 4 shows a poppet valve in which the heat conducting metal isapplied thereto in the form of a solid sleeve.

Referring to the drawing, the valve is in every case of the orthodoxtype having a cylindrical stem 2 and a head 3 at one end thereof.

The heat conducting metal is applied to the exterior of the valve, andaccording to the arrangement shown in Figure 1, the valve stem 2 isgrooved externally as at I3 to receive copper or like metal wire I4which is wrapped round the grooves and subsequently machined fiush withthe surface of the stem. In the modification of this arrangementillustrated in Figure 2,

' the wire I4, instead of being machined flush with the surface of thestem, is encased in a metal sleeve I5 which is forced over the turns.The advantage of this latter arrangement is that both the sleeve I5 and.the valve guide in which it reciprocates may be made of cast iron.

In the arrangement illustrated in Figure 3, the heat conducting metal isapplied to the ex-- terior of the valve in the form of a sleeve I6 madeof closely coiled copper or other suitable wire or strip. The internaldiameter of said sleeve is a push fit on the valve stem 2 and, as willbe seen, the sleeve itself is encased in a bush I! one end I8 of whichis flared to make a close joint with the neck of the valve whilst theother end is formed with an inwardly directed flange I9 which fitsclosely around the valve stem and retains the coiled wire sleeve I6 inposition. In this figure the valve guide is indicated at 20. For thepurpose of preventing relative axial movement of the sleeve I6 and. bushII on the valve stem 2 the latter, as shown, is formed adjacent theflange I9 of the bush with an annular groove 2| in which is located acircular spring 10 locking ring 22. Relative axial movement may also beprevented by spot Welding either end of the bush I! to the valve or inany other suitable manner.

In a further form, represented in Figure 4, the 15 heat conducting metalis applied to the valve in the form of a tubular sleeve or bush 23 ofsolid copper or other suitable good conductor of heat, the sleeve orbush being introduced onto the valve stem 2 with a driving fit. 0

In another method included in the present invention a heavy coating ofcopper or other heat conducting metal is applied to the exterior of thevalve either by a process of electro-deposition or in the molten stateby a spraying process. 25

I claim:

1. A valve for internal combustion engines comprising a head, acylindrical stem, a coiled Wire sleeve introduced onto said stem, andmade of a metal having a higher degree of heat con- 30 ductivity thanthat of the metal of the valve, and a bush adapted to enclose saidsleeve.

2. A valve for internal combustion engines comprising a head, acylindrical stem, a sleeve on said stem made of a metal having a higher35 degree of heat conductivity than that of the metal of the valve, abush adapted to encase said sleeve, an inwardly projecting flange at oneend of said bush which fits closely around the stem, and a locking ringlocated in a groove in said 40 stem to prevent axial movement of saidsleeve and bush.

3. The combination with the stem of a poppet valve, of a sleeveintroduced about the exterior of said stem and made of a metal having ahigher 45 degree of heat conductivity than that of the metal of thevalve, and a bush adapted to enclose and protect said sleeve.

FRANK ERNEST BULLOCK.

